you will need to purchase bulkhead fittings to seal the holes. you can buy them relatively cheap online, if your local hardware store does not have them. also, you can buy the screens for them online too. the hole will need to be slightly larger than the bulkhead fitting.
beyond that, the drain and return plumbing are the same.

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why buy, when you can DIY

well, this weekend i will attempt to go to my lhs and ask them the questions about the drilling and stand.

hopefully you'll be around if i have any questions regarding the overflow plumbing and return pump.

oh and:
would i need bulkhead fittings for the drilled holes on the sides of the tanks?

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you will need a bulkhead fitting regardless of where you drill the hole. the bulkhead fitting is the seal between the tank and the plumbing.
a pair of 1" bulkhead fittings will be easy to find, and will be way more than enough for your tank.

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why buy, when you can DIY

yeah i understand i'll need those for the overflow, if i get overflow holes drilled in. but i'm speaking of the drilled holes i'll have on the sides of the tank(for the fish passageway)

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oh those. idk, ive never done it personally.
if the cylinder connecting the tanks is a snug fit and goes through the glass (as opposed to just connecting to the outside of the glass), i would imagine you would be able to seal it with a good silicon.
make sure its glass, not acrylic.

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why buy, when you can DIY

i'll make sure to ask that when i go to my lhs.
edit: could i get any glass cylinder, or would i have to get one with the same thickness as my tank? - i'll probably get something slightly thicker than my tank glass to ensure my tank from not breaking around those parts.

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I am looking at your design and wondering why 20g talls? the water level is only going to go as high as your lowest tank when you have them connected... if you overfill the 20s the 30 will overflow or the 20s will only have about 15g in each instead of the full 20 and this may look tacky... go with same heighted tanks that way you have a seamless water level.

sorry, i didnt know this was already said... as you were. lol.

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If its not broke dont fix it!!! If its broke save yourself the time and buy a new one!!!

yeah. when i found this out i tried to look for a tank with the same length as a 20g tall. the only one small enough to fit this design is a 30g tall(i THINK) it may be long, not tall - someone clear this up for me, thanks.

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again, im not positive, as i have never done it. but i would imagine as long as its the same thickness, you will be fine.

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why buy, when you can DIY

i'll have to make a list of questions when i go over to my local hardware store, ha ha.

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The stand would be more intricate if you wanted to use those exact sized tanks i was thinking you could put the 30 on a pedestal in the middle. And one canopy to cover them all would be nasty

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If its not broke dont fix it!!! If its broke save yourself the time and buy a new one!!!

well. i don't plan on using a canopy. and if i put the 30 on a pedestal i would have to change the way i drill the holes on the sides of the tanks.

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You might have to do some minor adjustments. But besides the pipe sitting a little higher on the 20H rather than in the middle, its all the same really

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why buy, when you can DIY

i'm sure there will be many adjustments. but right now my main concern is finding out if there is somewhere near my location where i can purchase glass cylinders/tubing.

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just in case i'm not able to find a glass shop(that sells glass tubing) near my location and have to change my entire plannings--

how would i be able to build myself a tank? what materials would be needed? i'm sure i can locate a window shop and ask for a **x** sized glass window for the tank. just need to know out of what i need to build the tank of(wood/iron/etc) and why that specific kind of material.

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You're better off just getting a second hand 55-75g tank. You can probably get one for next to nothing on craigslist. The glass alone will cost you more than just buying a tank already built.

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why buy, when you can DIY

like i said before on one of the above posts(near the original post) i said my luck on CL isn't good. i can't manage to find a 55g or above relitively cheap, or alone for that matter(just the tank and hood/light)

i've searched my yellow pages and called a few glass companies and it seems only one company near my location does custom glass cuts. only problem is they wont pick up so i'll have to drive down. if luck is on my side, they might be able to cut me some cylinders.

but if all goes wrong, i might actually just make my own tank. i have a 60 inch wide wall to work with, and i'd like to construct a tank about 222g, if not 151g. so i'm trying to figure out the height and length to acheive a 22 or 151g tank.

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